SanDisk Extreme SSD 240 GB Review

SanDisk Extreme SSD uses SF-2281 controller and 24 nm flash memory made by SanDisk. We have never a seen a combination like that before, so it is particularly interesting to check it out and see if contemporary Toggle Mode NAND will be able to breathe new life into the second-generation SandForce based platform.

SandForce series controllers have acquired a lot of opponents among users. Some still remember that early SandForce-based SSDs used to be plagued by stability issues. Others do not like the performance hit such SSDs suffer as they transition from their out-of-box into steady state. SandForce controllers are even regarded as cheats because their performance depends on the type of processed data and SSD makers try to conceal this fact, specifying the best-scenarios speed only.

On the other hand, there is no denying the fact that SandForce-based SSDs are hugely popular. The developers of this hardware platform have managed to please both SSD makers and SSD users. The former are enticed by the simplicity and flexibility of the SandForce solution whereas the latter are ready to put up with its downsides as long as it offers an excellent price/performance ratio. So, if you take a look at any price list with PC components, you are sure to find the SSD category occupied by SandForce-based products.

Recalling our numerous reviews of SSDs with SF-2281/SF-2282 controllers, we can categorize all such products into four groups. The first one includes SSDs from Intel with exclusive firmware which makes them faster than other brands’ SSDs with the same hardware (synchronous flash memory with ONFI interface). The second group includes a lot of reference-design SSDs with the same hardware as Intel’s but with reference firmware. The third group is comprised of SSDs with asynchronous flash memory that are slow but cheap. And the fourth and smallest group includes rather fast SSDs in which the SandForce controller works with Toggle Mode NAND flash memory.

This classification helped easily sort out any consumer-class SSDs with SF-2281/SF2282 controllers in terms of performance, so we could often avoid benchmarking a new SSD in depth by simply pointing at its similarity to products tested earlier. However, the situation seems to be changing, so the SandForce platform needs a new look.

These changes result from the fact that 32 nm flash memory with Toggle Mode interface, employed for the fourth-group SSDs according to our classification, has been all used up. The manufacturers of such memory, Toshiba and SanDisk in the first place, have long transitioned to more progressive technologies, 19 and 24 nm. The natural outcome of this situation is the emergence of a new class of SandForce-based SSDs which use such memory. Today we’ve got the first SSD that combines the good old SandForce SF-2281 controller with new 24 nm Toggle Mode flash. The innovative product is called SanDisk Extreme SSD.

So, the maker of Toggle Mode MLC NAND flash is itself promoting the new SSD design. That’s important for end-users since, being the manufacturer of most of the SSD’s components, SanDisk should have more headroom for price maneuvering. The Extreme SSD may turn out to be an extremely attractive offer, so let’s check it out right now.